Identification and Isolation of Novel Sugar-Like RNA Protecting Materials: Glycylglycerins from Pluripotent Stem Cells.

Pluripotent stem cells are a resourceful treasure box for regenerative medicine. They contain a large variety of novel materials useful for designing and developing new medicines and therapies directed against many aging-associated degenerative disorders, including Alzheimer's disease, Parkinson's disease, stroke, diabetes, osteoporosis, and cancers. Currently, identification of these novel stem cell-specific materials is one of major breakthroughs in the field of stem cell research. Particularly, since the discovery of induced pluripotent stem cells (iPSC) in year 2006, the methods of iPSC derivation further provide an unlimited resource for screening, isolating, and even producing theses novel stem cell-specific materials in vitro. Using iPSCs, we can now prepare high quality and quantity of pure stem cell-specific agents for testing their therapeutic functions in treating various illnesses. These newly found stem cell-specific agents are divided into four major categories, including proteins, saccharides, nucleic acids, and small molecules (chemicals). In this article, we herein disclose one of the methodologies for isolating and purifying glycylglycerins-a group of glycylated sugar alcohols that protect hairpin-like microRNA precursors (pre-miRNA) and some of tRNAs in pluripotent stem cells. In view of such a unique RNA-protecting feature, glycylglycerins may be used to preserve and deliver functional small RNAs, such as pre-miRNAs and small interfering RNAs (siRNA), into human cells for eliciting their specific RNA interference (RNAi) effects, which may greatly advance the use of RNAi technology for treating human diseases.